The present invention relates to sprinklers used in automatic fire extinguishing systems for buildings and the like, and in particular, to a compact pendant sprinkler head assembly.
Sprinkler heads have long been used in automatic fire extinguishing systems for buildings and the like in order to disburse a fluid to suppress or extinguish a fire. Typically, the fluid utilized in such systems is water, although systems have been developed to disburse foam and other materials. Historically, sprinkler heads include a solid metal base connected to a pressurized water source, and a deflector intended to alter the trajectory of the water and distribute the water spray pattern over a controlled area. The deflector is typically spaced from the base outlet, and a fusible trigger assembly secures a seal over the base outlet. When the temperature about the sprinkler head is elevated to a preselected temperature indicative of a fire, the fusible trigger assembly releases the seal, and water flow is initiated through the sprinkler head. The water ejected from the sprinkler head impacts the deflector, resulting in a preselected water distribution pattern which descends upon the fire.
One common sprinkler head design is a pendant sprinkler head, whereby the sprinkler head is positioned in a downward direction towards the floor of the controlled area. With such pendant sprinkler heads, normally, the deflector is positioned a preselected distance below the outlet of the sprinkler body, and is secured to a pair of arms extending away from outlet of the sprinkler body. In response to the activation of the fusible trigger assembly, the sealing assembly falls away from the sprinkler body, allowing water to be transported through the sprinkler body in a downward direction towards the deflector.
The deflector in many current pendant sprinkler head designs is positioned a fixed distance from the outlet of the sprinkler body, and thereby increases the size of the sprinkler head. Furthermore, in many applications, aesthetic considerations demand that the sprinkler body is compact and relatively unnoticeable. In addition, many applications require an effective, compact sprinkler head in order to maximize space utilization. Current pendant sprinkler heads are generally incapable of being used under such conditions, as the size and particular structural configuration yields a sprinkler head which is conspicuously noticeable, as well as relatively large.
In response, the industry has advanced pendant sprinkler heads which are designed to be recessed within a ceiling or other wall. These recessed pendant sprinklers often include a deflector positioned between the fusible trigger assembly and the outlet of the sprinkler. Upon separation of the fusible trigger assembly, the water pressure travelling through the orifice of the sprinkler head moves the deflector a preselected distance away from the outlet. The deflector is normally attached to two or more vertically extending rods or pins slidably received by apertures formed in a flange or rim projecting from the exterior surface of the sprinkler head. The free end of each pin is formed with an increased diameter, and thus, as the water pressure forces the deflector away from the outlet, the pin ends abuttingly contact the flange or rim to hold the deflector in place.
The use of pins to enable the deflector to move a preselected distance from the outlet upon activation of the sprinkler head, and the flanges or rim into which they are slidingly positioned have certain disadvantages. The pins, as they are external to the sprinkler body can gather dust, particulate matter, or fluids residing within the wall or ceiling into which the pendent sprinkler head is attached. This dirt and debris may collect within the apertures formed within the flange or rim and prevent the efficient and smooth movement of the pins through the aperture in response to a fire, and in consequence, prevent the proper operation of the sprinkler head. In addition, the pin receiving flanges or rim projecting from the sprinkler body necessarily requires the cavity of the wall or ceiling into which the sprinkler is placed to be larger in diameter. That is, to enable clearance of the rim or flange, the hole through which the pendent sprinkler head is inserted must be larger. This in turn prevents such pendent sprinkler heads from being used in environments wherein efficient use of space is required.
Accordingly, there exists a need for a high volume pendant sprinkler head which is compact to thereby enable use in applications wherein effective space utilization must be observed.